Fuel strainer with magnet



June. 1954 H. w. RUNDQUIST ETAL 2,680,519

FUEL STRAINER WITH MAGNET Filed Aug. 9, 1950 3nventors attorneys Patented June 8, 1954 Y UNITED STATES PATENT OFFICE 2,680,519 FUEL STRAINER WITH MAGNET Henning W. Rundquist, East Lansing, and Gilbert Burrell, Lansing, Mich., assignors to General Motors Corporation, Detroit, Mich., a corporatron of Delaware Application August 9, 1950, Serial No. 178,524 Claims. (01. 2101.5) This invention relates to improved magnetic has openings to provide for flow past the magnet strainers and more particularly to improved to the fuel strainer. magnetic fuel strainer for use in the fuel system A further object of the invention is to provide In automotive use, the problem of cleaning the netic attraction and having apertures adjacent now employed. These carburetors have finer These and other objects of the invention will nozzles and thus make the fuel filtering or strainbe apparent from the following specification and ing problem more critical. Due to the fine nozzles, 1 drawing.

pressure has increased and the strainer elements to show details of the fuel strainer and magnet. become clogged quicker. In many applications, Figure 2 is a cross section of Figure 1 on the line the deposit on the surface of the strainer element 22 showing the top of the filter element consisted largely of small iron particles It was Flgure 3 1s a cross sectlon of Figure 1 on the found that this problem could be solved by placline 33 showing the bottom of the filter element mg a magnet in the inlet flow stream of the Figure4isapartialsectionalview ofamodified strainer. Thus substantially all the fluid enterfilter element with a magnet.

ing the strainer passed sufliciently close to the Figure 5 is a cross section of Figure 4 on the magnet so that any lI'OIl particles would be atline 5-,: showing the bottom of the filter element tracted to the magnet before they reached the The invention is illustrated in a fuel strainer provide an entrance passage opening into the ably secured to an aperture i8 in the side of the other end of the cylindrical filter element there fuel inlet passage 20 which extends downwardly is an annular end plate to hold the filter element in the center of the annular recess I4. At one side in position. The end plate has a diametrically in the annular recess 14 an outlet passage 22 exextending bar to support the magnet centrally tends upwardly to the pumping chamber (not within the strainer element. When the fluid shown) within the housing It.

and around the magnet before contacting the nular plate 24 which has a peripheral offset seat face of the strainer element and therefore the annular recess. The plate 24 has a central aper- A primary object of the invention is to provide portion 34 which provides a seal by engaging the an improved fuel strainer with a magnet located ner lip 35 0 the a nu ar ecess- The strainer in the fluid inlet path so that magnetic materials element 35 consists of a plurality of annular washers. The apertures 44 of each washer 38 are aligned to provide a plurality of vertical passages extending through the stack of filter washers. The filter support washer All positioned at the bottom of the stack of filter washers is not apertured and therefore seals the lower ends of the vertical passages. The support plate 24 has apertures at aligned with each of the vertical passages formed by the apertures 44 in the filter washers 38 to provide outlet for the filtered fluid.

The filter support plate 40 has a transverse bar 48 extending diametrically across the plate. A small cylindrical magnet 50 is positioned at'the center of the plate which is made of anonmagnetic material. The magnet has a central aperture 52 so that a rivet may be employed. to secure the magnet 50 to the support bar it. The semi-circular apertures 56 positioned on each side of the support bar 48 guide the flow of the unfiltered fiuid so that it passes close to the magnet 50 and any magnetic impurities will be removed.

The strainer and magnet assembly is enclosed in a glass bowl 58 whose top edge engages the seal 23. An abutment E8 seats in a recess in the lower portion of the glass bowl and is engaged by the adjustable thumb wheel 62 and screw 64. The screw hasa slotted head 6'5 to receive the bail 68 which is pivotally attached to the sides of the lower pump housing l2 in the conventional manner.

A modified mounting for a magnet mounted within a fuel strainer of this type is illustrated in Figures 4 and 5. fhe fuel strainer is again mounted on-the lower portion 12 of the fuel pump housing. The fuel pump housing has an'lnlet 28 from the fuel supply and outlet 22 to the pump chamber. filter element 35 consisting of a plurality of filter 38 is mounted-on'a plate 24. lower plate. 12 is substantially solid and has a central recess which provides a pocket for the cylindrical magnet.- The plate i2 ismade of a magnetic material, such as iron, so that the magnet 16 will'hold itself in position bymagnetic attraction. The upper plate 24 and the filter washers and the plate 12 have suitably aligned apertures to receive the rivets 42 which are employed to secure the assembly together. plate 12 has an aperture 'idhaving the shape of an annular segment positioned on each side of the recess and magnet 16-to direct the fiow of the unfiltered fluid over the magnet. This strainer assembly may be similarlyhoused in a glass bowl 5B sealed to the pump body portion l2 by gasket 23. The bowl 58 is held in position by abutment 6t and the adjustable wheel 62 and screw 64 which engage the conventional bail 6B.

When the pump it is in operation, th fluid from a suitable source of supply is drawn through the pipe 16' and enters through the passage to the top center of the strainer bowl. The fluid passes over and around the magnet 50 so that all magnetic particles in the fuel are separated and attach themselves to the magnet. The apertures 55 in the lower plate 40 guide part of the fluid over the magnet 50. The filtered fluid is then cleared of magnetic particles which wouldclog the surface of the filter washers 38 and the fluid fiowsbetween or through the washers 38 to the passage M to the outlet passage 22. In a modified formof. the invention, the fluid flows through the strainer and magnet element inthe same The * the plate 12 serving manner. The lower plate 12 of the filter element is made of a ferrous material so that the magnet 1'6 holds itself in position in the recess 'Hi. The plate 12 is closely adjacent the magnet 16 in order to guide the flow of fluid over the magnet to collect the magnetic metal particles before they deposit on the filter element. It will be. noted that the openings in the plate '12 are quite small and their small size results in more effectively as a baffle to prevent any particles which may collect in the bottom of the bowl from being stirred up and drawn to the filter element where they would tend to clog the: filter element and reduce its life.

The preferred embodiments of the invention have been illustrated in the above specification It will be apparent that many modifications may be made within the scope of the invention as defined by the appended claims.

Weclaim:

1. In a combination strainer and magnetic separator, a housing, an inlet opening at the top center of said housing, an outletopening in said housing, an annular strainer element secured to said'housing and sealed to saidhousing around the inletopening, said annular strainer element having central drainage passages spacedaround said annular filter for the filtered fluid, means connecting said central-drainage passages to said outlet opening, a magnetic material support member secured to the baseof said filter element, a rod-like magnet secured to said magnetic material member entirely by magnetic attraction in the" path of the incoming unfiltered fluid, and mechanical means to prevent lateral movement of said magnet.

2. In a combination strainer and magnetic separator, a housing, an inlet opening at the top center'of said housing, an outlet opening in said housing; an annular strainer element secured to said housing and sealed to said housing around the inlet opening, said annular strainer element having central drainage passages for the filtered fluid; means connecting said central drainage passages spaced around said annular filter to saidoutlet opening, a magnetic material support member having a central recess secured to the base of said filter element, and a rod-like magnet positioned in said recess to limit lateral movement and secured entirely by magnetic attraction to said bar in the path of the incoming unfiltered fiuid.

3. In a strainer, a housing having an inlet and an outlet opening, a strainer element having one surface contacting unfiltered fluid and another surface contacting filtered fluid positioned between said inlet and outlet openings and supported on said housing, said strainer element dividing said' housing into an inlet chamber facing said one surface and an outlet chamber facin said another surface, means to connect said inlet opening directly to the unfiltered fiuidchamber of said housing and to connect the outlet opening to filtered fluidportion of said housing, an elongated rod-like magnet supported on said housing entirely by magnetic attraction, said magnet being positioned. within. said housing directly opposite. said. inlet opening and extending coaxially toward. said inlet. opening and terminating a short distancefromsaid inlet opening and having afree end-portionfacing said inlet opening in the path of the unfiltered fiuid.

4. In a strainer, .a housing having aninlet and connect said inlet opening directly to the unfil- $316? Other said housin and located coaxially with respect 2508 656 30 to said inlet opening, sald strainer element having eleme' bein end of said strainer, said one end of said strainer g supported adjacent and on said end housing, a backing Washer secured to end of the said strainer element and to said support portion and extending from said of said strainer element toward said one end of said strainer element and terminating References Cited in the file of this patent UNITED STATES PATENTS Name Date Rohrbach May 17, 1938 Frei Mar. 7, 1939 Babitch May 23, 1939 Feagin May 7, 1946 Frantz May 23, 1950 

